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Investigating Genotype 1a HCV Drug Resistance in NS5A Region via Bayesian Inference

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Tsinghua Science and Technology 2015年第5期20卷 484-490页

作者： yao fu Gang Chen Lizhi fu Jing Zhang bioinformatics scientist in Bina Technologies Roche Redwood City CA 94065 USA the financial service industry Department of Mathematics & Statistics Georgia State University the Department of Statistics Yale University

Hepatitis C virus（HCV） treatment is on the cutting edge of medicine. Due to the high rate of mutations and low fidelity of HCV replication, resistant strains quickly become dominant in a viral population under the selection pressure of a drug. In this paper, we examined the drug resistance mechanism in the NS5 A region of genotype1 a HCV virus by comparing the sequence data from interferon-ribavirin treated and untreated patients. To find the drug resistance difference, we used innovative Bayesian probability models to detect mutation combinations and inferred detailed interaction structures of these mutations. We aim to provide reference to drug design and mutation mechanism understanding through our work.

关键词： Bayesian model Hepatitis C virus(HCV) drug resistance NS5A

Preparation and thermal stability of Pd_(40.5)Ni_(40.5)Si_xP_(19-x) bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 204-207页

作者： Yang Li yao-cen Wang Ke-fu yao Department of Mechanical Engineering Tsinghua University Beijing 100084 China

With the addition of Si to replace some P,Pd40.5Ni40.5SixP19-x（x=0,2.5,5,9.5,14,and 19 in atomic number fraction） bulk glassy samples with the diameter of about 5 mm were successfully prepared by use of flux treatment and water quenching *** the increase of Si content,the glass forming ability of Pd40.5Ni40.5Si-xP19-x increases first for low Si content and then decreases for high Si content （Si≥9.5at%）.The Pd40.50Ni40.5Si5P14 glassy alloy possesses the largest supercooled liquid region△T of 119 K,the largest reduced glass transition temperature of 0.621,and the largestγparameter of 0.460,indicating that this glassy alloy possesses very large glass forming ability and very high thermal stability.

关键词： bulk metallic glass flux method glass forming ability water quenching thermal stability

Effective conversion of cellobiose and glucose to sorbitol using non-noble bimetallic NiCo/HZSM-5 catalyst

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Science China Chemistry 2018年第9期61卷 1167-1174页

作者： Bakht Zada Long Yan yao fu Hefei National Laboratory for Physical Science at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) CAS Key Laboratory of Urban Pollutant Conversion Anhui Province Key Laboratory for Biomass Clean Energy and Department of Chemistry University of Science and Technology of China

The tandem hydrolysis and hydrogenation of saccharides into sorbitol is an especially attractive reaction in the conversion of biomass. Here, an economical and efficient bimetallic catalyst for the transformation of glucose and cellobiose into sorbitol is reported. Non-precious metal based catalysts such as NiCo, Ni, and Co, were prepared via modified impregnation method, and NiCo/HZSM-5 showed superior performance for the synthesis of sorbitol(86.9% from cellobiose, 98.6% from D-glucose).Various characterizations, such as Brunner-Emmet-Teler(BET), X-ray diffraction(XRD), transmission electron microscopy(TEM) and X-ray photoelectron spectroscopy(XPS), confirmed that NiCo alloy formed and highly dispersed in NiCo/HZSM-5 catalyst. The high performance of fabricated catalyst would be attributed to the formation of nickel-cobalt alloy over HZSM-5 zeolite surface. High temperature and H_2 pressure were favorable for the tandem hydrolysis and hydrogenation reaction. Besides,the reaction pathway was also proposed based on the kinetics study. Cellobitol was detected as the intermediate in the reaction mixture. furthermore, in the catalytic stability study, it was found that active metal species of NiCo/HZSM-5 were stable. The deactivation of catalyst would be due to the covering of acidic sites over NiCo/HZSM-5.

关键词： biomass sorbitol glucose cellobiose bimetallic catalyst

Maluta's Coefficient of Musielak-Orlicz Sequence Spaces

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Acta Mathematica Sinica,English Series 2005年第4期21卷 699-704页

作者： Hui Li yao Ting fu WANG Department of Mathematics Harbin University of Science and Technology Harbin 150080. P. R. China

In this paper, we give the formula of Maluta＇s coefficient for calculation, and don＇t add any conditions to the generating function Ф.

关键词： Maluta's coefficient Musielak-Orlicz sequence spaces

Mechanistic study of copper-catalyzed intramolecular ortho-C-H activation/carbon-nitrogen and carbon-oxygen cyclizations

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Science China Chemistry 2013年第5期56卷 619-632页

作者： TANG ShiYa GONG TianJun fu yao Department of Chemistry University of Science and Technology of China

Intramolecular ortho-C-H activation and C-N/C-O cyclizations of phenyl amidines and amides have recently been achieved under Cu catalysis. These reactions provide important examples of Cu-catalyzed functionalization of inert C-H bonds, but their mechanisms remain poorly understood. In the present study the several possible mechanisms including electrophilic aro- matic substitution, concerted metalation-deprotonation （CMD）, Friedel-Crafts mechanism, radical mechanism, and proton- coupled electron transfer have been theoretically examined. Cu（II）-assisted CMD mechanism is found to be the most feasible for both C-O and C-N cyclizations. This mechanism includes three steps, i.e. CMD with Cu（II）, oxidation of the Cu（II） inter- mediate, and reductive elimination from Cu（III）. Our calculations show that Cu（II） mediates the C-H activation through an six-membered ring CMD transition state similar to that proposed for many Pd-catalyzed C-H activation reactions. It is also in- teresting to find that the rate-limiting steps are different for C-N and C-O cyclizations： for the former it is concerted metalation-deprotonation with Cu（II）, whereas for the latter it is reductive elimination from Cu（III）. The above conclusions are consistent with the experimental kinetic isotope effects （1.0 and 2.1 for C-O and C-N cyclizations, respectively）, substituent effects, and the reactions under O2-free conditions.

关键词： mechanism DFT copper C-H activation concerted metalation-deprotonation

Photoinduced Dehalocyclization to Access Oxindoles Using Formate as a Reductant

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Chinese Journal of Chemistry 2024年第11期42卷 1203-1208页

作者： Wei Ge Jia-Xin Wang Ming-Chen fu yao fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefeiAnhui230026 China Anhui Province Key Laboratory of Value-Added Catalytic Conversion and Reaction Engineering Hefei University of TechnologyHefeiAnhui230009 China

Herein,we report an efficient and practical protocol for the photoinduced dehalocyclization of ortho-halophenylacrylamides with formate by the engagement of a CO_(2) radical anion to access substituted *** method proceeds smoothly under mild conditions and exhibits a wide range of substrate as well as remarkable functional group compatibility.

关键词： Formate CO_(2)Radical ions Oxindole Photocatalysts Cyclization Organohalides

Bibliometric analysis of the literature from the mainland of China on animal-derived regenerative implantable medical devices

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Frontiers of Materials Science 2014年第4期8卷 403-408页

作者： Hong-Man WANG fu-yao LI Institute for Medical Humanities Peking University Health Science Center Beijing 100191 China

Choosing animal-derived regenerative implantable medical devices based on tissue engineering technology as a research theme, this paper presents bibliometric analysis of relative literature from the mainland of China to understand such data as publication year and journal preference, authors＇ geographic location, research topics and core expertise to predict the research trends and provide an informed basis of decision making for researchers and clinicians.

关键词： animal-derived medical device tissue engineering regenerative implan-table medical device literature China's Mainland bibliometric analysis

Redox potentials of trifluoromethyl-containing compounds

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Science China Chemistry 2015年第4期58卷 673-683页

作者： Yuanye Jiang Haizhu Yu yao fu Lei Liu Department of Chemistry University of Science and Technology of China Department of Polymer Science and Engineering University of Science and Technology Beijing Department of Chemistry Tsinghua University

Trifluoromethylation reactions are important transformations in the research and development of drugs, agrochemicals and functional materials. An oxidation/reduction process of trifluoromethyl-containing compounds is thought to be involved in many recently tested catalytic trifluoromethylation reactions. To provide helpful physical chemical data for mechanistic studies on trifluoromethylation reactions, the redox potentials of a variety of trifluoromethyl-containing compounds and trifluoro- methylated radicals were studied by quantum-chemical methods. First, eoB97X-D was found to be a reliable method in predicting the ionization potentials, electron affinities, bond dissociation enthalpies and redox potentials of trifluoromethylcontaining compounds. One-electron absolute redox potentials of 79 trifluoromethyl substrates and 107 trifluoromethylated radicals in acetonitrile were then calculated with this method. The theoretical results were found to be helpful for interpreting experimental observations such as the relative reaction efficiency of different trifluoromethylation reagents. Finally, the bond dissociation free energies （BDFE） of various compounds were found to have a good linear relationship with the related bond dissociation enthalpies （BDE）. Based on this observation, a convenient method was proposed to predict one-electron redox potentials of neutral molecules.

关键词： trifluoromethylation redox potential density functional theory

Preparation of transparent TiO_2 nanocrystalline film for UV sensor

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Chinese Science Bulletin 2006年第14期51卷 1657-1661页

作者： fu yao CAO Wanghe Optoelectronic Technology Institute Dalian Maritime University Dalian116026 China

nanocrystalline TiO_2 电影电极被大音阶的第五音胶化方法在不同锻烧的温度准备，它有不同电影厚度，一致透明性，以及光电的高度和机械稳定性的特征。光电的大小证明那锻烧的温度和电影厚度能显著地影响电极的光电的性质。在 450 deg... 详细信息

nanocrystalline TiO_2 电影电极被大音阶的第五音胶化方法在不同锻烧的温度准备，它有不同电影厚度，一致透明性，以及光电的高度和机械稳定性的特征。光电的大小证明那锻烧的温度和电影厚度能显著地影响电极的光电的性质。在 450 deg C 锻烧的电影是有 highcrystallinity 和强壮的光电的活动的锐钛矿阶段，并且显示出最大的光电流。当温度比 450 deg C 低时，因为很多缺点，这部电影在这部电影有更弱的结晶度，并且这不为 pho-togenerated 搬运人的运输是有利的。并且在比 450 deg C 高的温度，电极的光电流被减少在这部电影的到期的 toanatase 金红石阶段转变。电影厚度的增加对紫外光的改进有利(紫外) 吸收总计，它将改进这部电影的光电的活动。但是，过多的厚度将在电极在减小增加 theelectron 洞对，和结果的再结合率“ s photoelectric 活动。另外，在电极生产的光电流的反应敏感和稳定性与偏爱潜力有关。在 0.4 V 的一个潜力，电极显示出 30.8 亩 Aand 的浸透的光电流 ~ 的一反应时间 1 s，建议准备 TiO_2 拍摄电极能被用于做紫外传感器。

关键词：无机非金属材料功能材料纳米Ti02薄膜远红外传感器制备